A sensor of this kind is known from U.S. Pat. No. 4,342,907 describes an optical sensor for the measurement of stress, temperature, pressure, etc. by means of an optical fiber. This optical fiber can be deformed so that the transmission of light therein is modified. With reference to FIG. 11, the cited document describes a sensor enabling the detection of externally applied pressures. It is formed by two half-cylindrical solid parts which apply the pressure to the optical fiber which is thus deformed. However, notably because of the constituent half-cylindrical solid parts the described sensor cannot constitute a cable which can be wound and deformed. Moreover, nothing is disclosed as regards its suitability for burial in the ground or as regards its detectivity in such operating conditions.
The problem to be solved in the realization of a pressure sensor which is capable of providing perimeter protection of a site in order to detect the presence of an intruder whose weight acts on the sensor without him knowing so, the sensor being intended for large sites so that ease of manipulation and installation by non-expert personnel are necessary.